05 Tahoe ,112k,2nd owner has thrown these codes.Wasn’t shifting into 4th/overdrive when it happened.Drove it home about 10 miles at about 50 mph and parked it. Next day started it and it shifted fine.Took it to shop and had it scanned.PO785 &P2761.Noticed when it shifts into 4th I hear a weird noise like scrubbing @ about 45 mph then slow down to about 40 when it downshifts and the noise goes away.So took to tranny shop and had him drive it and he thinks it’s my torque converter.
PO785 & P2761
- Thread starter Pepper
- Start date
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Found this and seems to cover many many codes that can pop up:
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the vehicle. Cause The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit.
Was there any recent work, of any kind, done to the vehicle?
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the vehicle. Cause The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit.
Was there any recent work, of any kind, done to the vehicle?
MassHoe04
Full Access Member
Won't cost anything to take a look at wires and connectors, to see if there is any obvious damage or loose connections any where. If you can get under and look around, it is wort a shot.
Guys when I bought the one-owner I did a CARFAX and @ 32k and 33k the vehicle was taken to the dealer for these codes but dealer took advantage of the elderly couple and cleared the codes .Got this information from the seller yesterday.I even explained to him at the time 32k,33k ,2007 both times it was under full warranty.So again I asked him how many times did it do this. He said its been 15 years but probably about 1/2 dozen or more.Each time he took to them and it wasn’t acting up,just throwing these codes.So now I’am the owner and dealing with it.IT WILL GET FIXED @ MY EXPENSE. But I joined this forum to HELP others and to get HELP.Thx for everyone and HAPPY THANKSGIVING !!
Won't cost anything but a little time to look at the hot level and condition of the tranny fluid. Reddish pink? Brown? Smells burnt?
swathdiver
Full Access Member
These two codes are issues with the valve body solenoids. This may be cleared up with clean fluid or it might be time to overhaul the valve body and the wiring. The wiring eventually gets contaminated with transmission fluid and this causes all kinds of electrical gremlins that will either annoy you or destroy the transmission.
Appreciate the feedback.??? Would this issue create a
(faint grinding noise) when it shifts into 4th gear and go away when it downshifts into 3rd.That’s the only time you hear this sound that something isn’t right.
swathdiver
Full Access Member
Can't say for sure. I can speculate that those noises are happening because those parts want fluid and the solenoids aren't delivering it.
rockola1971
Full Access Member
Check your pan for excessive amounts of what looks like brake dust. The 2-4 band could be slipping in 4th. A band aid that might save you is replace the oem servo with a corvette servo. But around 120k is usually the time that the tranny has to be completely overhauled and you are close to it.
Rockola1971 I may have mis spoken,not sure.The noise (similar to BAD bearing ONLY comes when the 4th gear is engaged. There is no jerking nothing u would notice unless u was told to listen to.For example with the windows up on a fairly quiet road then accelerate fairly slow to normal start to listen when it shifts into 4th.Once it needs to down shift to 3rd it completely goes away.To me(fwiw) the shifts are tight .I’ve pondered while @ 32k and 33k and couple more still under warranty ( CARFAX)
Engine/Powertrain Computer/Module checked.
IMO they new there was an issue but did nothing to resolve the issues.
Everyone that has responded has FAR more knowledge than me. I’m getting it fixed it’s just frustrating finding the shop I can trust.I could probably drop the pan and look for and (brake dust) material .My intentions are to get another shop to drive it and see what they say.The previous shop heard the noise and said the grinding
like sound was the TC.He said he doesn’t like just replacing the TC because if the problem comes back it gives his business a bad rap.So I will get a 2nd. opinion or 3rd. and go from there. I’m more frustrated that the owner let the dealership take advantage of him.BTW, I wasn’t listening for that noise when I bought it.Drove it probably 1000k before it didn’t shift into 4th. It’s happened twice since I’ve owned it.Both times it would reset before I could get it to the tranny shop.1st time I drove it back home (10 miles) then the 2nd time I pulled into a parking lot and turned it off and it worked fine accept for the noise.
Again to everyone on this site Thanks for your input and my explanations.
Engine/Powertrain Computer/Module checked.
IMO they new there was an issue but did nothing to resolve the issues.
Everyone that has responded has FAR more knowledge than me. I’m getting it fixed it’s just frustrating finding the shop I can trust.I could probably drop the pan and look for and (brake dust) material .My intentions are to get another shop to drive it and see what they say.The previous shop heard the noise and said the grinding
like sound was the TC.He said he doesn’t like just replacing the TC because if the problem comes back it gives his business a bad rap.So I will get a 2nd. opinion or 3rd. and go from there. I’m more frustrated that the owner let the dealership take advantage of him.BTW, I wasn’t listening for that noise when I bought it.Drove it probably 1000k before it didn’t shift into 4th. It’s happened twice since I’ve owned it.Both times it would reset before I could get it to the tranny shop.1st time I drove it back home (10 miles) then the 2nd time I pulled into a parking lot and turned it off and it worked fine accept for the noise.
Again to everyone on this site Thanks for your input and my explanations.
